1. Field of the Invention
The present invention relates to a supporting system for supporting elongate conductors and, more particularly, to a device for containing the conductors in a bearer element of the supporting system.
2. Brief Description of Prior Developments
This invention relates to supporting means for elongated building services supply means. Service supply means may be low voltage electric power cables (for example, such as cables rated for 50 Volts or less), communication cables, water or gas pipes or other elongated conductors for the supply or distribution of services within a building. Such supporting means necessarily include one or more bearer elements on which the service supply means rest. Typically the bearer element has been the floor of a tray or trough fixedly associated with the building being serviced, for example carried by wall brackets or suspended from a ceiling or other overhead building component by tie rods or the like. Probably, the most frequently occurring service supply means are electric cables; namely, data and signal communication transmission wires or cables. For that reason, supporting means are usually referred to in the art as xe2x80x9ccable traysxe2x80x9d; irrespective of the service supply means that may be supported in any instance (notwithstanding recent departures in the form of the bearer elements from that of an integral floor of a traditional tray or trough). When convenient the term xe2x80x9ccable traysxe2x80x9d is used accordingly hereinafter.
As stated above, traditionally the bearer elements of cable trays comprised the floor of a shallow trough or elongated tray. The service supply means resided within the trough. The trough, including its floor, was constructed from sheet material, for example steel, plastics or fibrous cement. Alternatively, at least the floor of the trough has been made of expanded metal sheet. This is preferred as it eliminates the possibility of the trough retaining water or detritus that may be damaging to the service supply means.
In other instances floor-like bearer elements came to be replaced by a plurality of spaced apart rungs extending between rigid stiles. The wall brackets or tie rods are affixed to the stiles, so that the supporting means as a whole resemble a conventional ladder in a substantially horizontal disposition. Such ladder-like supporting means are still customarily referred to as cable trays.
In more recent times, the stiles of such ladder-like cable trays have been replaced by a central spine, and the rungs by a plurality of spaced apart bearer elements extending as cantilevers from each side of the spine. The bearer elements preferably have upturned free end parts, so as to retain the service supply means. This is advantageous as the service supply means may be placed on the bearer elements from the sides, instead of having to be pulled into position from one end of the cable tray.
The last mentioned prior art is well exemplified by the published specification of Australian Patent application 99/943515 and the international publication WO 98/24160 of International application PCT/AU/00788 (both in the name of Ramset Fasteners (Aust) Pty Ltd). In that cited prior art, the spine is a rectangular sectioned tube, and the cantilever bearer elements extend through clearance openings piercing the tube walls. It is apparent that the upturned free ends of the cantilever bearer elements are formed after the elements have been passed through those openings, otherwise it would not be possible to put them in place. This is disadvantageous, as it would require expensive manual operations or the use of complex special purpose machines in the manufacture of the cited prior art cable trays.
In accordance with one aspect of the present invention, a combined safety clip and closure device is provided for a conductor support. The combined safety clip and closure device includes a first restraining section and at least one closure section. The first restraining section is adapted to be located at, and restrain movement of, at least one spring clip deflectable tongue of the conductor support. The spring clip is mountable to a spine of the conductor support. The closure section extends from the first restraining section. The closure section extends outward from the first restraining section a majority of its length.
In accordance with another aspect of the present invention, a closure device is provided for closing an entrance into a conductor bearer element for an elongate conductor. The closure device comprises a center section; and a connecting system. The connecting system comprises a main connector and at least one outer end connector with at least a portion of the center section being located therebetween. The main connector is adapted to connect to a spine mount of the bearer element. The outer end connector is adapted to adjustably connect to an outer end of a cantilevered arm of the bearer element.
In accordance with another aspect of the present invention, an elongate conductor support system is provided comprising a support frame comprising a spine; and a plurality of bearer elements connectable to the spine. Each bearer element comprising a spine mounting section and at least one cantilevered arm extending laterally outward from the spine mounting section. The cantilevered arm comprises an upturned end. The spine mounting section comprises two upwardly extending spaced tongues with an inwardly extending stud on at least one of the tongues. The stud has a slot extending upward into the stud to form a receiving area for receiving a portion of the spine therein.
In accordance with another aspect of the present invention, a safety clip is provided for a snap lock mount of a bearer element to a spine in an elongate conductor support system. The safety clip comprises a main connector section comprising two apertures for receiving top portions of snap lock tongues of the snap lock mount of the bearer element; and a snap lock peg.
The snap lock peg extends downwardly from the main connector section for directly attaching the safety clip to the spine. The snap lock peg comprising a general mushroom shape with a dome section and a stem section. The dome section is suitably sized and shaped to be press fit through a hole in the spine to snap lock mount the safety clip to the spine.
In accordance with one method of the present invention, a method of connecting an elongate conductor bearer element to a spine in an elongate conductor support system is provided comprising steps of connecting a main connection section of the bearer element to the spine; and connecting a closure device to the bearer element comprising mounting a safety clip section of the closure device to top ends of tongues of the main connection section, and covering a majority of a top side opening into a conductor receiving area of the bearer element by a portion of the closure device.
In accordance with another method of the present invention, a method is provided for connecting a closure device to a bearer element of an elongate conductor support system comprising steps of: connecting a safety clip section of the closure device to a spine mounting section of the bearer element; and adjustably connecting an outer end connector of the closure device to an upstanding end of a cantilevered leg of the bearer element. A portion of the closure device closes an opening through a top side of the bearer element into a conductor receiving area. The size of the receiving area can be varied by the adjustable connection of the outer end connector of the closure device to the upstanding end of the bearer element.
The invention is well adapted for use in relation to cable trays comprising a single spine and a plurality of discrete cantilever bearer elements, although it will be apparent to those skilled in the art that it is also applicable to ladder-like cable trays having two or more parallel spines and a plurality of discrete rung-like bearer elements.
Supporting means for elongated building service supply means can comprise at least one spine and a plurality of discrete bearer elements affixed to said at least one spine. Each bearer element can be affixed to said at least one spine by a spring clip fixedly associated with said each bearer element. For preference the spring clip is formed integrally with its associated bearer element.
The supporting means can form at least an equal plurality of locating formations on said spine, each able to be engaged by a co-acting locating formation on a said spring clip to thereafter resist disengagement of the bearer elements from the spine.
The spine can be an inverted channel section comprising a channel web and two channel flanges, said locating formations comprise a longitudinally extending row of spaced apart holes in each of the channel flanges, each spring clip comprises two upwardly directed, spaced apart resilient tongues projecting from the clip""s associated bearer element, each with a barb formation at or near its free end directed towards the other, and each with a stud intermediate its ends projecting towards the other constituting said co-acting locating formations; the arrangement being such that the tongues of each clip may clasp the spine between them with the barbs of the tongues overlying respective margins of the channel web and with the studs on each tongue extending into a respective hole in the adjacent channel flange.
Furthermore, for preference, in the last mentioned embodiments each bearer element can define a groove at or near the root of each of its tongues in which a free edge margin of the adjacent channel flange is received when the barb formations overlie the margins of the channel web and the studs are homed in the holes.